In my experience, the months that are the worst for biting are the months actually leading up to getting that first tooth. It's amazing how hard a baby can gum the nipple! Once they have teeth, at least in my cases, things got better.
I have, however, had 2 babies that thought it amusing to bit my shoulders or behind my knees. Odd, I know. I never quite figured this out and they were older when they did this. My son was about 18 months old, if I remember right. He would come up and bite the backs of my knees while I washed dishes. And Darcy was probably around the same age, or maybe closer to 12 months. It put me on edge all the time, anticipating the next bite. If you have a baby biting while nursing, I know exactly what you're feeling -- physically, mentally, and emotionally. If you cannot relax during breastfeeding, this can affect milk let-down. So let's see what we can do to help.
I have received a couple of Facebook messages lately that I'd like to share:
The obvious, "Ow! NO!" and removing baby from breast is a normal reaction. I was just talking with a friend of mine tonight about this and she said that was the first and last time her baby bit her. On the other hand, if baby is startled enough and scared by your reaction, he may start a nursing strike where he's scared to resume nursing. This may last even a few days! I don't believe the baby is being mean. It probably feels good to bite down on something. You might try a cool washcloth before nursing. Let him suck on that for a few minutes. It may numb the gums enough that he doesn't have that need to bite down.
Another trick I remember trying was to plug baby's nose when they would bite. Seems mean, but they have to breathe and they will release the nipple. I like this one because they can see your face and you can see theirs. Immediately end the nursing. Resume when you both feel ready, maybe in 5 minutes, or maybe in 5 hours! I also read about pushing the baby into the breast, but I don't like this idea. You can't see their face and this may cause them to bite harder. The idea was the same as the nose squeezing, making them release the breast because they can't breathe. The other, in my opinion, is more effective. I think that is an unpleasant association for the baby to bite and then not be able to breathe, and this is why we didn't have this problem very long.
My favorite lactation consultant in the DFW area, Mellanie Sheppard of For Babies Sake, suggested the following link: "This is is my favorite teething advice when babies are "chewing" like that (not just nipping at the end of a feeding)." Mellanie has told me time and again that www.kellymom.com is her favorite breastfeeding website.
I hope this is helpful. Sometimes misery loves company, doesn't it? There is comfort in knowing that other moms (nearly all of us) go through this at some point. This won't last forever, but you can't let the baby bite you either. Maybe it's time to turn off the Twilight movies, at least until baby is asleep!